pub fn new_count_distinct(input_str: &str) -> usize {
    let mut count = 0;
    let mut chars = input_str.split(",");
    let mut char_set = std::collections::HashSet::new();
    while let Some(c) = chars.next() {
        if!char_set.contains(&c) {
            char_set.insert(c);
            count += 1;
        }
    }
    count
}
